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CVE-2017-20227: Varaneckas Jad Java Decompiler: Buffer overflow

CVE-2017-20227 is rated critical with a CVSS v3.1 base score of 9.8 and affects Varaneckas Jad Java Decompiler. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

JAD Java Decompiler 1.5.8e-1kali1 and prior contains a stack-based buffer overflow vulnerability that allows attackers to execute arbitrary code by supplying overly long input that exceeds buffer boundaries. Attackers can craft malicious input passed to the jad command to overflow the stack and execute a return-oriented programming chain that spawns a shell.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

• Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
• Attack complexity: Low. No special conditions; the attack can be repeated reliably.
• Privileges required: None. No account or prior access is needed.
• User interaction: None. No action from any user is needed.
• Scope: Unchanged. Impact stays within the vulnerable component.
• Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
• Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
• Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-787: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

Affected products

• Varaneckas Jad Java Decompiler: 1.5.8e-1kali1

References

• https://www.vulncheck.com/advisories/jad-8e-1kali1-stack-based-buffer-overflow
• https://www.exploit-db.com/exploits/42255
• http://www.varaneckas.com/jad/